LICE. 393 



CASE of the hard parts, such as the claws, and especially in their 

 teeth. 



In some, as in those from the European, the Caffre, and the 

 Japanese, the teeth are scarcely visible. In others, from the 

 Hindu, Indian of the Andes, &:c., they are numerous, large, and 

 almost tubercular. In others, from the negro and King George 

 Sound Australian, they are limited to two or three well-marked 

 serrations. The form and proportions of what may be called 

 the thumb, are also different. In some, as the Mozambique 

 Africander, Californian Indian, and Indian of the Andes, it is 

 excessively developed ; in others, as the European, the Japanese, 

 and Australian, only moderately so. The form of the penultimate 

 joint also varies to a very considerable extent, in some being 

 long, narrow, elongate and straight ; while in others it is conical, 

 curved, short, and broad at the base. 



But then comes the question, what is the value of these 

 differences as bearing upon the unity of the human species ? It 

 has been proved that there are differences, and that these differ- 

 ences are constant and permanent — that is no doubt something, 

 But, unluckily, these difTerences are most singularly similar to the 

 differences in the races whose unity is the question in dispute, 



Claw of Pediculus capitis, from North American Ditto, from Australian. 



Indian of Slave Lake. 



and to solve which this evidence has been adduced. If we can- 

 not believe that the negro is a different species from the European, 



